1. Field of the Invention
The present invention relates to a controller for a plurality of sets of flash lamps sharing a common power source. The present invention also relates to a method for controlling selective discharge of the flash lamps.
2. Description of the Related Art
Flash lamps have been widely used in, e.g., photographing, alarm, advertisement, stage performance, or decoration. For stage performance or advertisement, as illustrated in FIG. 3 of the drawings, several identical and individual sets of flash lamps are used. Each set of flash lamps consists of a high-voltage charging/discharging circuit 50 and a flashing circuit 60. The high-voltage charging/discharging circuit 50 comprises two diodes 51 and 52, two capacitors 53 and 54, and a choke coil 55 for supplying the flashing circuit 60 with high-voltage power. The flashing circuit 60 comprises a flash lamp 61, an activating coil 66, a resistor 64, a capacitor 65, a silicon controlled rectifier 63, and a neon lamp 62. A timed self-activating flashing effect is provided by using the characteristic of conduction of the neon lamp 62 only when a pre-determined voltage is reached and the delay characteristic provided by the resistor 64 while charging the capacitor 65. Namely, variable flashing effects can be obtained by setting the resistive-capacitor time constants of all of the sets of flash lamps to be slightly different from each other or in a pre-determined manner.
However, every set of flash lamps requires an independent high-voltage charging/discharging circuit 50. The overall device occupies a considerable space and the efficiency is poor, for the flash lamps do not illuminate continuously. Instead, the flash lamps merely provide brief, momentary flashing. More particularly, most of time, the high-voltage charging/discharging circuit is charged and thus ready for discharging. Namely, the efficiency of use of each high-voltage charging/discharging circuit 50 is very low.
It is an object of the present invention to provide a controller for a plurality of sets of flash lamps that share a common power source. The controller comprises only one high-voltage charging/discharging circuit and a plurality of flashing circuits that share the high-voltage charging/discharging circuit. The volume of the overall device can be reduced by 40% and the overall cost is also reduced.
It is another object of the present invention to provide a controller for a plurality of sets of flash lamps that share a common power source, wherein irregular self-activating type flash lamp sets can be obtained if each set of flash lamps is set to be in a mode that the neon lamp controls the self-activating flashing circuit by means of using a single high-voltage charging/discharging circuit.
It is a further object of the present invention to provide a controller for a plurality of sets of flash lamps that share a common power source, wherein program-controlled self-activating type flash lamp sets can be obtained by means of using a single high-voltage charging/discharging circuit that cooperates with a programmable controller and providing a signal decoder in each flashing circuit.
It is still another object of the present invention to provide a method for controlling a plurality of sets of flash lamps that share a common power source, the method comprising the steps of:
(a) providing a high-voltage charging/discharging circuit, the high-voltage charging/discharging circuit being a voltage-increasing loop comprising two diodes, two capacitors, and a choke coil;
(b) providing a plurality of sets of flashing circuits, each said set of flashing circuit being a self-activating flashing circuit comprising a resistive-capacitor charging circuit, an activating coil, a silicon controlled rectifier, and a flash lamp, each said set of flashing circuit including a power source end that is electrically connected to an output end of the high-voltage charging/discharging circuit; and
(c) selectively discharging the plurality of sets of flashing circuits by the high-voltage charging/discharging circuit under time-sharing control.
In accordance with the present invention, a controller is provided for a plurality of sets of flash lamps that shares a common power source, the controller comprising:
a high-voltage charging/discharging circuit, the high-voltage charging/discharging circuit being a voltage-increasing loop comprising two diodes, two capacitors, and a choke coil; and
a plurality of sets of flashing circuits, each said set of flashing circuit being a self-activating flashing circuit comprising a resistive-capacitor charging circuit, an activating coil, a silicon controlled rectifier, and a flash lamp, each said set of flashing circuit including a power source end that is electrically connected to an output end of the high-voltage charging/discharging circuit.
Each flashing circuit includes a neon lamp mounted to the input end thereof, thereby forming a controller for irregular self-activating type flash lamp sets.
In an alternative embodiment, each flashing circuit includes a decoder mounted to the input end thereof, thereby forming a controller for program-controlled self-activating type flash lamp sets. A programmable controller outputs a signal for each flashing circuit. A direct current stabilizing circuit has an output end connected to the programmable controller and each flashing circuit.
Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.